MM74C922
MM74C922 is 16 / 20-Key Encoder manufactured by National.
MM54C922 MM74C922 16-Key Encoder MM54C923 MM74C923 20-Key Encoder
July 1993
MM54C922 MM74C922 16-Key Encoder MM54C923 MM74C923 20-Key Encoder
General Description
These CMOS key encoders provide all the necessary logic to fully encode an array of SPST switches The keyboard scan can be implemented by either an external clock or external capacitor These encoders also have on-chip pullup devices which permit switches with up to 50 kX on resistance to be used No diodes in the switch array are needed to eliminate ghost switches The internal debounce circuit needs only a single external capacitor and can be defeated by omitting the capacitor A Data Available output goes to a high level when a...